On Wed, 19 Sep 2018 at 04:11, Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > In the quest to remove all stack VLA usage from the kernel[1], this > replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage > with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), > which uses a fixed stack size. > > [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@xxxxxxxxxxxxxx > > Cc: Jens Axboe <axboe@xxxxxxxxx> > Cc: linux-block@xxxxxxxxxxxxxxx > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > --- > drivers/block/cryptoloop.c | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/drivers/block/cryptoloop.c b/drivers/block/cryptoloop.c > index 7033a4beda66..254ee7d54e91 100644 > --- a/drivers/block/cryptoloop.c > +++ b/drivers/block/cryptoloop.c > @@ -45,7 +45,7 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) > char cms[LO_NAME_SIZE]; /* cipher-mode string */ > char *mode; > char *cmsp = cms; /* c-m string pointer */ > - struct crypto_skcipher *tfm; > + struct crypto_sync_skcipher *tfm; > > /* encryption breaks for non sector aligned offsets */ > > @@ -80,13 +80,13 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) > *cmsp++ = ')'; > *cmsp = 0; > > - tfm = crypto_alloc_skcipher(cms, 0, CRYPTO_ALG_ASYNC); > + tfm = crypto_alloc_sync_skcipher(cms, 0, 0); > if (IS_ERR(tfm)) > return PTR_ERR(tfm); > > - err = crypto_skcipher_setkey(tfm, info->lo_encrypt_key, > - info->lo_encrypt_key_size); > - > + err = crypto_sync_skcipher_setkey(tfm, info->lo_encrypt_key, > + info->lo_encrypt_key_size); > + > if (err != 0) > goto out_free_tfm; > > @@ -94,7 +94,7 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) > return 0; > > out_free_tfm: > - crypto_free_skcipher(tfm); > + crypto_free_sync_skcipher(tfm); > > out: > return err; > @@ -109,8 +109,8 @@ cryptoloop_transfer(struct loop_device *lo, int cmd, > struct page *loop_page, unsigned loop_off, > int size, sector_t IV) > { > - struct crypto_skcipher *tfm = lo->key_data; > - SKCIPHER_REQUEST_ON_STACK(req, tfm); > + struct crypto_sync_skcipher *tfm = lo->key_data; > + SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm); > struct scatterlist sg_out; > struct scatterlist sg_in; > > @@ -119,7 +119,7 @@ cryptoloop_transfer(struct loop_device *lo, int cmd, > unsigned in_offs, out_offs; > int err; > > - skcipher_request_set_tfm(req, tfm); > + skcipher_request_set_sync_tfm(req, tfm); > skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, > NULL, NULL); > Does this work? > @@ -175,9 +175,9 @@ cryptoloop_ioctl(struct loop_device *lo, int cmd, unsigned long arg) > static int > cryptoloop_release(struct loop_device *lo) > { > - struct crypto_skcipher *tfm = lo->key_data; > + struct crypto_sync_skcipher *tfm = lo->key_data; > if (tfm != NULL) { > - crypto_free_skcipher(tfm); > + crypto_free_sync_skcipher(tfm); > lo->key_data = NULL; > return 0; > } > -- > 2.17.1 >
